This is a note to let you know that I've just added the patch titled
io_uring: Use original task for req identity in io_identity_cow()
to the 5.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
io_uring-use-original-task-for-req-identity-in-io_identity_cow.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From lee@xxxxxxxxxx Sat Jul 23 15:54:25 2022
From: Lee Jones <lee@xxxxxxxxxx>
Date: Tue, 19 Jul 2022 12:52:51 +0100
Subject: io_uring: Use original task for req identity in io_identity_cow()
To: lee@xxxxxxxxxx
Cc: stable@xxxxxxxxxxxxxxx, Jens Axboe <axboe@xxxxxxxxx>, Pavel Begunkov <asml.silence@xxxxxxxxx>, Alexander Viro <viro@xxxxxxxxxxxxxxxxxx>, io-uring@xxxxxxxxxxxxxxx, linux-fsdevel@xxxxxxxxxxxxxxx
Message-ID: <20220719115251.441526-1-lee@xxxxxxxxxx>
From: Lee Jones <lee@xxxxxxxxxx>
This issue is conceptually identical to the one fixed in 29f077d07051
("io_uring: always use original task when preparing req identity"), so
rather than reinvent the wheel, I'm shamelessly quoting the commit
message from that patch - thanks Jens:
"If the ring is setup with IORING_SETUP_IOPOLL and we have more than
one task doing submissions on a ring, we can up in a situation where
we assign the context from the current task rather than the request
originator.
Always use req->task rather than assume it's the same as current.
No upstream patch exists for this issue, as only older kernels with
the non-native workers have this problem."
Cc: Jens Axboe <axboe@xxxxxxxxx>
Cc: Pavel Begunkov <asml.silence@xxxxxxxxx>
Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: io-uring@xxxxxxxxxxxxxxx
Cc: linux-fsdevel@xxxxxxxxxxxxxxx
Fixes: 5c3462cfd123b ("io_uring: store io_identity in io_uring_task")
Signed-off-by: Lee Jones <lee@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/io_uring.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -1325,7 +1325,7 @@ static void io_req_clean_work(struct io_
*/
static bool io_identity_cow(struct io_kiocb *req)
{
- struct io_uring_task *tctx = current->io_uring;
+ struct io_uring_task *tctx = req->task->io_uring;
const struct cred *creds = NULL;
struct io_identity *id;
Patches currently in stable-queue which might be from lee@xxxxxxxxxx are
queue-5.10/io_uring-use-original-task-for-req-identity-in-io_identity_cow.patch
